The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) system has been designed to offer significantly higher data rates, higher system throughput, and lower latency for delay critical services than existing telecommunication systems. This improved performance has to be provided and guaranteed during various mobility conditions. For example, there is a requirement for mobility support with high performance up to speeds of 120 km/h. A further requirement is the uninterrupted provision of high data rates and services, often referred to as Guaranteed Bit Rate (GBR) services. Hence, handover (HO) and its performance during such conditions are of high importance.
In US2001055969, there is disclosed a method and apparatus for handoff to a rescue channel without the need to send and receive handoff control messages. The method provides coordination of the rescue procedure at the infrastructure and mobile station. In a step, the mobile transmitter is disabled followed by subsequent detection of signal loss and frame erasures at the serving cells. Further, the mobile transmitter is enabled followed by subsequent detection of signal by a rescue cell. Finally, the rescue cell channel transmitter is enabled followed by subsequent detection and reception of signal and frames by the mobile station. A disadvantage with this solution is that there is a too long delay before the mobile station may respond to bad channel conditions and, hence recover from signal loss.